ARS | Publication request: Stability and broad-sense heritability of mineral content in potato: zinc

Submitted to: American Journal of Potato Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 27, 2011
Publication Date: February 27, 2011
Citation: Brown, C.R., Haynes, K.G., Moore, M., Pavek, M., Hane, D., Love, S., Novy, R.G., Miller, J.C. 2011. Stability and Broad-sense Heritability of Mineral Content in Potato: Zinc. American Journal of Potato Research. 88:238-241.

Interpretive Summary: Zinc is an important micronutrient in the human diet. The poorest of the worlds population epxerience zinc deficiency among a portion of the population. The irichest sources are animal proteins, which escape the purchasing power of poor people. Siginficantly, millions also eat vegetrian diets for religious reasons. Zinc is recommended as a palliative remedy in cases of diarrheal diseases and pneumonia. An estimated 1 million people die from complicagtions due to zinc deficiency each year. An international effort to biofortify beta-carotene, zinc, iron and selenium in crop plants has been in force for a decade. We evalauted a number of advanced breeding lines and cultivars for zinc content. We found that the content of zinc ranged from 12 to 18 micrograms per gram dry wieght. Also in two of the groups of clones the probability of selecting for higher zinc was low, while in one group the probabilibty was high. Even so the range of zinc expression is only 50 percent higher than the minimum value. The clone with the highest zinc content would only supply 3 percent of the recommended daily allowance for adults. It appears that potato is not a good candidate for increasing zinc to a point where it could substantially alleviate deficiency.

Technical Abstract: The mineral content of potato is an important consideration in the evaluation of its role in the human diet. Zinc content is vital due to its crucial role as a micronutrient. Zinc deficiency occurs among the poorest of the world’s populations. In this study36 breeding lines and varieties divided among three groups of were grown in 11 locations. Zinc content was measured in harvested tubers by wet ashing and passage through an Inductively Coupled Argon Plasma Emission Spectorphotometer. The values in genotype means ranged from 12 to 18 micrograms per gram dry weight over all trials. In two trials genotype was not a significant source of variation. Broad sense heritabilities were small for these trials. In the Western Regional Russet Trial genotype was significant and the heritability was 0.61, suggesting that selection among clones would make substantial progress in raising zinc content The range of values is only 50 percent above the low value. Furthermore, a hundred gram serving of the highest zinc genotype would only provide 3 percent of the adult recommended daily allowance. From these results potato would not appear to be a good candidate for biofortification of zinc through traditional breeding.